Pin connections and functions SRK2001A
4/20 DocID029495 Rev 1
2 Pin connections and functions
Figure 3. Pin connections (top view)
Table 2. Pin functions
No. Name Function
1VCC
Supply voltage of the device. A bypass capacitor to GND, located as close to IC's pins
as possible, helps to get a clean supply voltage for the internal control circuitry and
acts as an effective energy buffer for the pulsed gate drive currents.
2GND
Return of the device bias current and return of the gate drive currents. Route this pin
to the common point where the source terminals of both synchronous rectifier
MOSFETs are connected.
3
(8)
GD1
(GD2)
Gate driver output for section 1 (2). Each totem pole output stage is able to drive
power MOSFETs with high peak current levels. To avoid excessive gate voltages in
case the device is supplied with a high V
CC
, the high-level voltage of these pins is
clamped to about 11 V. The pin has to be connected directly to the SR MOSFET gate
terminal.
4
(7)
SVS1
(SVS2)
Source voltage sensing for section 1 (2): it is the reference voltage of the
corresponding drain sensing signal on the DVS1,2 pin. These pins have to be
connected directly to the respective source terminals of the corresponding
synchronous rectifier MOSFET.
5
(6)
DVS1
(DVS2)
Drain voltage sensing for section 1 (2). These pins have to be connected to the
respective drain terminals of the corresponding synchronous rectifier MOSFET using
a series resistor of 100 .
9PROG
Programming pin for conduction duty-cycle at burst-mode exiting. A resistor
connected from this pin to GND, supplied by an internal precise current source, sets a
voltage V
PROG
; depending on this voltage level, during the start-up phase, the user
can choose, according to the application requirements, the proper burst-mode exiting
conduction duty-cycle among the ones contained in an internal lookup table which
values are reported in Table 6: Burst-mode exiting lookup table on page 15 (the
values are predefined inside the table). For the proper choice of the resistor value see
Table 5: Electrical characteristics.
10 EN
Enable pin function with internal pull-up (remote ON/OFF): during the run mode, when
the pin voltage is sensed below the internal threshold V
EN_OFF
, the controller stops
operating and enters a low consumption state; it resumes the operation if the pin
voltage surpasses the threshold V
EN_ON
.
